This invention has to do with differential gear assemblies for automobiles trucks and the like, and more particularly, is concerned with differential gear assemblies of increased durability and reliability by virtue of a novel asymmetric arrangement of not less than three pinions in differential engagement with the bevel gears used to transmit power from the propeller shaft drive pinion to the wheel axles.
Differential gear assemblies serve to compensate for different distances traveled by wheels on the inside and outside of a curve. In transmitting power to the wheels of an automobile, a propeller shaft driven by the engine through the gear box drives a ring gear at right angles to the propeller shaft to convert the rotation of the longitudinal power shaft to rotation of the transverse wheel axles. As will be evident upon consideration, a wheel on the outside of a curve travels farther in the same amount of time than the inner wheel opposite it and thus, if tire scuffing is to be avoided, it must rotate relatively faster than the inner wheel. The use of differential gearing to accomplish this result is known. Essentially the "differential," comprising a case, pinions and pinion shafts coupled to the ring gear, turns as a unit along a straightaway but pinions rotate on their axes relative to one another to compensate for the different distances traveled by the inner and outer wheels in turning.